Cephalexin: The Generic Name for a Well-Known Antibiotic
Cephalexin is the generic name for a widely-used antibiotic that falls into the first-generation cephalosporin class. While many people recognize it by its former brand name, Keflex, the drug itself is now primarily sold and referred to by its generic name. As a prescription medication, cephalexin is effective against a variety of bacterial infections but does not treat viral illnesses like the common cold or flu. The widespread availability of the generic version has made this treatment more affordable for many patients.
How Cephalexin Works
As a beta-lactam antibiotic, cephalexin works by targeting and inhibiting the synthesis of the bacterial cell wall. This crucial component provides mechanical stability to bacteria. By interfering with its formation, cephalexin effectively kills the bacteria or prevents their growth, allowing the body's immune system to clear the infection. However, bacteria can develop resistance over time, which is why it is critical to complete the full course of therapy as prescribed, even if symptoms improve early. Misuse or premature discontinuation can contribute to antibiotic resistance, making future infections harder to treat.
Common Uses for Cephalexin
Cephalexin is prescribed to treat a variety of bacterial infections in both adults and children over one year of age. Its uses include:
- Respiratory Tract Infections: Such as bacterial pneumonia and other upper respiratory issues.
- Ear Infections: Particularly otitis media.
- Skin and Skin Structure Infections: This can include conditions like cellulitis.
- Urinary Tract Infections (UTIs): Including acute and chronic infections.
- Bone Infections: Such as osteomyelitis.
- Dental Prophylaxis: It may also be used in certain cases before dental procedures to prevent infection.
Available Dosage Forms
Cephalexin comes in several oral forms, which allows for flexible and convenient dosing depending on the patient's age and specific needs. The common forms include:
- Capsules: Available in various strengths, such as 250 mg, 500 mg, and 750 mg.
- Tablets: Offered in strengths like 250 mg and 500 mg.
- Oral Suspension: A liquid form, typically available in concentrations like 125 mg/5 mL and 250 mg/5 mL, which is convenient for children or those who have difficulty swallowing pills. The suspension should be refrigerated and discarded after 14 days.
Potential Side Effects
While generally well-tolerated, cephalexin can cause side effects. It's important to be aware of these and to contact a healthcare provider if they persist or become severe.
Common side effects include:
- Diarrhea
- Nausea and vomiting
- Upset stomach or indigestion
- Dizziness
- Headache
- Genital or rectal itching
Serious side effects, though rare, can occur and require immediate medical attention:
- Severe allergic reaction: Symptoms include hives, swelling of the face, throat, or tongue, and difficulty breathing.
- C. difficile infection: This can cause severe, watery, or bloody diarrhea and stomach cramps, even months after treatment has ended.
- Blood disorders: Rare but potentially serious side effects can affect blood cell counts.
- Kidney problems: Use with caution in patients with pre-existing kidney issues.
Cephalexin vs. Other Common Cephalosporins
| Feature | Cephalexin (Oral) | Cefadroxil (Oral) | Ceftriaxone (Injectable) |
|---|---|---|---|
| Generation | First-generation | First-generation | Third-generation |
| Mechanism | Inhibits bacterial cell wall synthesis | Inhibits bacterial cell wall synthesis | Inhibits bacterial cell wall synthesis |
| Administration | Oral capsules, tablets, or suspension | Oral capsules, tablets, or suspension | Injection (into veins or muscle) |
| Frequency | 2 to 4 times a day | 1 to 2 times a day | Usually once a day |
| Common Uses | UTIs, skin infections, ear infections, respiratory tract infections | UTIs, skin infections | Severe infections, meningitis, gonorrhea, surgical prophylaxis |
| Severity of Use | Milder, more common bacterial infections | Mild infections | Often used for more severe or complicated infections |
Important Drug Interactions
Before taking cephalexin, inform your doctor about all other medications, vitamins, and supplements you are taking. Key interactions to be aware of include:
- Metformin: Cephalexin can increase the concentration of metformin in the body, potentially raising the risk of metformin side effects.
- Probenecid: This medication, which treats gout, can increase the level of cephalexin in the blood, increasing the risk of side effects.
- Warfarin: Use with this blood thinner requires careful monitoring, as cephalexin can affect its blood-clotting effects.
- Live Vaccines: The use of cephalexin can affect the effectiveness of certain live vaccines, such as the typhoid vaccine.
Conclusion
Ultimately, the question of what's the generic for cephalexin has a straightforward answer: its own name. Cephalexin is the generic, active ingredient found in what was once known as Keflex. This first-generation cephalosporin antibiotic remains a valuable and frequently prescribed treatment for a variety of common bacterial infections affecting the ears, skin, urinary tract, and respiratory system. Understanding its uses, potential side effects, and important interactions is vital for safe and effective treatment. Always complete the full course of medication as prescribed by your healthcare provider to ensure the infection is fully eradicated and to help prevent the development of antibiotic resistance.
